Precise construction of CVD Si/C composites: multi-scale strategies from liquid-electrolyte to solid-state lithium batteries

The relentless pursuit of high energy density lithium-ion batteries (LIBs) has intensified the development of silicon-based anodes, with Si-C composites synthesized via chemical vapor deposition (CVD) emerging as a promising candidate due to their balanced performance, scalability, and improved economic viability. Unlike conventional Si or SiOₓ anodes, CVD derived Si/C architectures feature covalently bonded, conformal carbon coatings and precisely engineered porous carbon scaffolds that simultaneously buffer volumetric strain, enhance transport kinetics, and stabilize interfacial chemistry. However, their practical deployment remains impeded by critical challenges, including internal interface debonding, SEI breathing failure, and performance degradation under demanding operational conditions. In this Perspective, we critically synthesize recent advances in multidimensional characterization, multiscale modeling, and interfacial engineering to elucidate the structure–property-performance relationships governing CVD Si/C anodes. We highlight innovative strategies, including hierarchical pore design, Si-C interfacial modulation, artificial SEI engineering, and synergistic prelithiation, which collectively suppress irreversible lithium loss, mitigate electrode swelling, and enhance interfacial resilience. Furthermore, we extend the discussion to solid-state battery integration, assessing how these anodes adapt to solid–solid interfaces. By bridging fundamental mechanisms with engineering solutions, this Perspective aims to accelerate the rational design and industrial adoption of robust, high-capacity Si/C anodes for next-generation energy storage systems.